<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>特效代码1</title>
    <link rel="stylesheet" href="../../css/bootstrap.css">
    <script src="../../js/bootstrap.js"></script>
    <style>
        .btn {
            padding-right: 80px;
            padding-left: 30px;
            border-radius: 0;
            color:#fff;
            text-transform: uppercase;
            background: #580141;
            overflow: hidden;
            position: relative;
            transition: all 0.3s ease 0s;
        }

        .btn:before{
            content: "";
            width: 33%;
            height: 200%;
            position: absolute;
            top: 0;
            right: 0;
            margin: -5px 0 0 -5px;
            transform: rotate(-20deg);
            transform-origin: 0 0 0;
            transition: all 0.3s ease 0s;
            z-index: 1;
        }

        .btn:after{
            content: "\f061";
            font-family: 'FontAwesome';
            position: absolute;
            top:25%;
            right: 13%;
            display: block;
        }

        .btn:hover:before{
            width: 40%;
        }

        .btn:hover{
            color:#fff;
        }
    </style>
</head>
<body>
<div class="container">
    <div class="row">
        <div class="col-sm-3">
            <a href="#" class="btn btn-lg purple">button</a>
        </div>
    </div>
</div>
</body>
</html>